JP2003121986A - Device and method for mask correction - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device and a method for mask correction which can quantitatively measure the shape of a defect formed on a photomask and correct the defect according to the defect shape. SOLUTION: This mask correcting device corrects the defect by irradiating the mask with a particle beam and can correct the mask without leaving any uncorrected part nor damaging a transparent substrate by irradiating the mask with the particle beam according to the shape of the defect.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mask repairing apparatus and a mask repairing method used for repairing a mask in a defect repairing process of a photomask used for manufacturing a semiconductor circuit.

[0002]

2. Description of the Related Art Defects that occur in the manufacturing process of a photomask used for forming a fine circuit pattern such as a semiconductor LSI circuit are roughly classified into black defects and white defects. FIG. 5 shows a schematic diagram schematically showing defects. Figure 5
5A and 5B are schematic diagrams of black defects.
(C), (d) is a schematic diagram of a white defect. The black defect is a residual defect in which unnecessary light-shielding film, foreign matter, and the like remain in a portion other than the normal pattern. The white defect is a defect defect in which a part of a normal pattern is missing or missing. When observed with transmitted light, black defects are blocked and appear black, and white defects appear transparent.

Depending on the size of the defect and the relative position to the pattern, the defect on the photomask can cause a fatal characteristic defect in the semiconductor circuit formed by transferring the circuit pattern on the photomask. Therefore, in order to manufacture a high quality semiconductor circuit, it is important to repair defects on the photomask as much as possible. That is, as the integration density of LSIs increases, a technique for correcting a fine circuit pattern and forming a photomask pattern with almost no defects is desired. However, in an actual photomask manufacturing process, it is extremely difficult to manufacture a defect-free mask from the beginning, which causes a significant decrease in yield. Therefore, the inspection is performed after the photomask is manufactured, and the defect is corrected.

In particular, as the degree of integration of LSIs has increased, the phase shift of light for exposure can be used to transfer a pattern with high resolution onto a wafer without exposing light of short wavelength. Shift masks are beginning to be used. When the semiconductor circuit is miniaturized and a photomask on which a fine pattern is formed has a defect, it is often difficult to sufficiently repair the photomask.

Various mask repairing devices and methods for repairing defects existing on a photomask having a fine pattern as described above have been disclosed. A dedicated repair device is used for mask defect repair work, but the repair method is different for black-based defects and white-based defects, and in many cases the devices are used separately. For example, to repair a black defect as shown in FIGS. 6A and 6B, the defect can be removed by irradiating the defect with a laser beam to evaporate the defect. However, the repair by laser irradiation may not be able to be repaired with high accuracy in some cases due to the relationship between the size of the defect and the wavelength of the laser beam used for repair. Therefore, when it is necessary to correct the pattern with high precision as the pattern becomes finer, the correction is performed using the gas assisted etching (GAE) technique by the focused ion beam (FIB) correction device. This is a technique for etching black defects by irradiating the defects with FIB while spraying a corrosive gas on the repaired portion. Further, in order to prevent the FIB irradiated on the defect from damaging the transparent substrate, the secondary ions of Cr used for pattern formation and Si constituting the transparent substrate are detected.
It also has an end point detection function that determines the irradiation conditions in the depth direction of B. Further, the FIB repair device is also used to repair the white defects as shown in FIGS. 5C and 5D, and the light-shielding film made of carbon is selectively volumed by the assisting action of the irradiation of the focused ion beam. The defect is repaired.

On the other hand, various means have been proposed as means for correcting defects formed on the photomask. For example, as disclosed in Japanese Unexamined Patent Publication No. 6-148870, the protrusion defect of a photomask having a phase shift mask layer is physically corrected by scratching the defect with a fine probe having a sharp tip. Defect repair methods are also known. However, the defect having a shape other than the convex defect cannot be removed, and the probe may be damaged in some cases. In addition, the defects may not be removed sufficiently.

As a method of repairing defects by non-contact, as disclosed in Japanese Patent Laid-Open No. 2000-347384, in order to repair defects in a photomask,
There is known a focused ion beam repairing apparatus and a defect evaluation method in which a focused ion beam repairing apparatus is provided with a method for judging exposure transferability. Specifically, using a photomask containing defects, a light intensity simulation means for quantitatively evaluating the exposure transferability of the photomask onto the wafer when the pattern is transferred such as a wafer to which the pattern is transferred. There is disclosed a repairing device for irradiating a defect with a focused ion beam based on the result of the exposure and transfer property simulation. In this case, after the photomask is repaired, the light intensity distribution is simulated again to re-evaluate the defect and repair the defect again. Errors such as defect shape may increase depending on the wavelength of the light to be exposed, and since the defect is not directly evaluated, the actual defect shape may not be confirmed with high accuracy, and the defect cannot be corrected sufficiently. There are cases. In particular, when a defect in a fine circuit is corrected based on the light intensity distribution due to exposure, the error between the actual defect shape and the simulation result may become large.

Further, as disclosed in Japanese Unexamined Patent Publication No. 2000-330261, there is a repair device provided with a method for judging exposure transferability in a laser repair device for repairing a defect of a photomask. Are known. Although the shape of a defect is detected by using the same exposure transfer property as in Japanese Patent Laid-Open No. 2000-347384, when a defect formed on a fine circuit is to be corrected, the wavelength of laser light is used to correct the defect. It may not be possible to make the wavelength sufficiently short, and it may not be possible to perform correction with sufficient accuracy.

Further, as disclosed in Japanese Unexamined Patent Publication No. 9-257445, in a FIB repairing apparatus, the height of a bump defect is measured by using a pulsed ion beam, and a photomask defect is repaired. Although a repairing method is also known, only a method for measuring the shape of a defect is described, and in particular, a method for repairing while sequentially measuring the three-dimensional shape of a defect during the repair of the defect is not mentioned.

[0010]

In order to realize the miniaturization of the accelerating LSI circuit pattern, there is a demand for a technique for correcting minute defects formed in the photomask pattern. In particular, in a photomask capable of transferring a fine pattern by shifting the phase, such as a halftone type phase shift mask and a Levenson type phase shift mask, it is possible to surely correct a minute defect to make a fine circuit. It is important to create patterns with good yield.

6 and 7 show specific examples of defects. FIG. 6 shows an example of a defect generated in the halftone phase shift mask. In the halftone type phase shift mask, the halftone shifter layer 112 is formed on the transparent substrate 111. The transparent substrate 111 is, for example, a light-transmissive Si.
O ₂ is used. FIG. 6 shows a halftone shifter layer 1
An example in which a halftone defect 113, which is a black defect attached when the halftone shifter layer 112 is formed, is formed on the exposed surface 114 of the transparent substrate 111 between the two. Not limited to black defects, halftone shifter layer 1
A white defect in which a part of 12 is missing may be formed.

When the defect 113 generated by the halftone type phase shift mass is irradiated with FIB and repaired by GAE, the component elements forming the halftone shifter layer 112 have a semi-transmissive property for transmitting a part of light. Therefore, C
Unlike the binary mask in which the shifter layer is formed by r, the end point during etching cannot be detected by using the secondary ions of Cr and Si contained in the transparent substrate. Therefore, when the defect 113 is repaired by GAE, there is a case where uncorrected residue or excessive irradiation of the focused ion beam on the transparent substrate 111 that constitutes the mask may damage the transparent substrate.

Further, since the correction conditions such as the irradiation amount and irradiation time of the focused ion beam are optimized by using the evaluation mask instead of the mask to be actually repaired, the shape of the defect to be actually repaired, or The transparent substrate that forms the mask when the irradiation conditions of the focused ion beam that is irradiated based on the material that constitutes the defect are not optimized and the defect is not sufficiently corrected, or because the focused ion beam is excessively irradiated. It may damage the.

Further, FIG. 7 shows an example of a defect generated in the Levenson type phase shift mask. In the Levenson-type phase shift mask, for example, the transparent substrate 121 is formed of SiO ₂ , and the light shielding film 122 is formed thereon with a material having low light transmittance such as Cr. A phase shifter is formed by removing the surface of the transparent substrate 121 exposed between the light shielding films 122 and forming the grooves 124. FIG. 7 shows a case where an unnecessary transparent protrusion defect 123 is formed in the groove portion 124. When the transparent protrusion-like defect 123 is repaired, the transparent substrate 121 and the transparent protrusion-like defect 123 have the same constituent elements.
_In the case of _2, it is impossible to detect the end point using the secondary ions, and it is difficult to detect the height of the protrusion defect 123 with high accuracy, and the focused ion beam of the focused ion beam is generated similarly to the halftone type phase shift mask. The transparent substrate 121 may be damaged due to excessive irradiation.

As described above, the problems at the time of repairing the two masks of the halftone type phase shift mask and the Levenson type phase shift mask have been mentioned. However, in the conventional FIB repairing method, even if the defect thickness is not uniform, it is uniform. Since the correction is performed, the focused ion beam is not irradiated based on the defect shape, and depending on the defect shape, an uncorrected portion or irradiation damage to the transparent substrate may occur.

Therefore, the present invention has been made in view of the above problems, and a mask repairing device capable of quantitatively observing a defect shape formed on a mask and repairing the defect based on the defect shape. Another object of the present invention is to provide a mask correction method.

[0017]

A mask repairing device of the present invention is a mask repairing device for repairing a defect by irradiating a mask with a focused ion beam, and a defect shape detecting means for detecting a three-dimensional shape of the defect. And defect correction amount conversion means for converting the three-dimensional shape data of the defect into the correction amount of the defect, and irradiating the focused ion beam based on the correction amount. The defect shape detecting means for detecting the defect existing on the mask detects the three-dimensional shape of the defect, and the irradiation condition of the focused ion beam is changed based on the data to accurately correct the defect. Can be done.

The mask repairing apparatus of the present invention comprises defect shape detecting means and defect repairing amount converting means for converting data relating to the shape of the defect, and changes the irradiation condition of the focused ion beam based on the shape of the defect. Can be done. At this time, it is possible to perform highly accurate correction by irradiating the focused ion beam. Further, it is possible to uniformly repair a defect having a non-uniform defect thickness, and it is possible to suppress uncorrected defects or irradiation damage to the transparent substrate depending on the defect shape.

Further, according to the mask correction method of the present invention,
While detecting the three-dimensional shape of the defect, the defect correction amount is calculated based on the data, and the focused ion beam irradiation conditions are changed based on the correction amount, so there is no defect remaining and the mask is corrected with high accuracy. It can be performed.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION The mask repairing apparatus and mask repairing method of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a configuration block diagram showing a configuration of a mask correction device when a focused ion beam is used as the focused ion beam.

First, the FIB ion source 5, the ion deflection system 6, the secondary ion detector 4, and the mask control stage 2 are arranged in the vacuum chamber 1. The photomask 3 is mounted on the mask control stage 2.

A material having a light-transmitting property is used for the substrate constituting the photomask 3. For example, when an inorganic material is used as the substrate, soda lime glass, quartz glass or the like can be used. Further, the photomask can be formed using not only an inorganic material but also polyester which is an organic material. In particular, in the case of a photomask having a fine pattern, it is preferable to use soda lime glass, quartz glass, or the like, which has a small coefficient of thermal expansion with temperature. Further, soda-lime glass and quartz glass are particularly preferable materials for a photomask for forming a fine pattern because they hardly change in size due to changes in humidity. When soda glass is used as the substrate material and a silver salt gelatin emulsion is used as the shifter layer, it is difficult to suppress defects and form a fine pattern. Mask modification is applied. It is also possible to use a photomask in which a chrome coating is patterned on a soda glass or quartz glass substrate. When a light-shielding film is formed with a chromium film, it has excellent mechanical strength, heat does not easily accumulate in the mask even after continuous exposure, and it is stable with no regressive properties, so it can withstand long-term use. , Reliable. In particular,
When quartz glass is used as the material of the substrate, it can be used for short wavelength exposure and can form a photomask having high dimensional stability.

As the FIB ion source 5, for example, a liquid
Metallic gallium (Ga) can be used. Liquid metal
Higher brightness than other ion sources as a feature of ion source
It can be mentioned that when compared by ion current density, liquid metal
The ion source is 3 to 6 orders of magnitude more ion than other ion sources.
Current can be obtained. Therefore, surface processing can be done in a short time.
Can be done at. It is emitted from the FIB ion source 5.
Gallium ion (Ga ⁺) Is accelerated by a two-stage focusing lens
And the beam diameter is focused. Then multiple deceleration lenses
The kinetic energy of Ga ions is suppressed by the
In the deflection system 6, the traveling direction of Ga ions is determined by the lack of the photomask 3.
Ga ions are irradiated to the defects in accordance with the depression.

When observing a defect, the focused ion beam is applied to the defect at a lower energy than the energy of the focused ion beam applied when the defect is repaired. At this time, secondary electrons are generated from the surface of the defect. By detecting this secondary electron with the secondary ion detector 4 and visualizing it,
Defects can be observed (this secondary electron image is SIM (S
It is called a "scanning Ion Microscope" image. ). In other words, the focused ion beam is irradiated near the defect with low irradiation energy, and the shape and position of the defect are confirmed by capturing the secondary electrons that fly out from the defect, and then the high-energy focused beam is used to correct the defect. The defect can be repaired by irradiating the defect with an ion beam. Further, since the focused ion beam can be finely processed by narrowing the beam diameter, the focused ion beam is not limited to be used for correcting the mask of the present embodiment, and a quantum dot laser using a quantum effect, other It is also an effective means for manufacturing quantum devices.

The FIB ion source 5 and the ion deflection system 6 are electrically connected to a control processor 8 arranged outside the vacuum chamber 1. Furthermore, the secondary ion detector 4 is electrically connected to the image observation means 7 outside the vacuum chamber 1, and the image observation means 7 is electrically connected to the control processor 8. The control processor 8 includes a defect correction amount conversion means 9 and a monitor 1.
0, an input unit 11, an output unit 12, and a defect information reading unit 13 are connected in parallel, and a defect shape detection unit 14 is electrically connected to the defect correction amount conversion unit 9. The monitor 10 is a screen on which an operator observes the shape of an imaged defect, and an image display device such as a CRT or a liquid crystal can be used. The input means 11 is a keyboard or the like for operating the mask correction device. Also,
The output unit 12 may be a printer for outputting defective image data or the like or a data writing device for writing data in a storage medium for storing the defective image data. For example, data can be written in various storage media such as magnetic recording media and optical recording media.

The defect shape detecting means 14 is connected to the mask correcting device via a carrying system. Defect shape detection means 1
Even if the defect is irradiated with the focused ion beam based on the detailed shape of the defect detected in 4, and the defect is being repaired, the defect shape detection unit 14 controls the defect shape data. The mask control stage 2 can be moved from the processor 8, and the defect can be reliably irradiated with the focused ion beam. Alternatively, of the portions forming the defect shape detection means 14, the detection unit for directly detecting the defect shape is provided in the vacuum chamber 1. Then, by the defect correction amount conversion means 9,
The defect shape data obtained by the defect shape detecting means 14 is converted into the correction amount of the area where the black defect should be removed and the area where the white defect should be replenished. Control processor 8
Through this, the irradiation conditions of the FIB ion beam are determined based on the correction amount, and the mask can be corrected by irradiating the defect with the FIB ion beam. Further, the position of the defect can be confirmed by imaging the signal of the secondary electrons sent from the secondary ion detector 4 to the image observing means 7, and the irradiation condition of the FIB ion beam can be determined based on that. I can.

The defect shape detecting means 14 will be described with a specific example. As the defect shape detection means 14, an atomic force microscope (AFM) is used.
The case of using the roscope) will be described. AFM
Is an apparatus capable of acquiring a three-dimensional image of the shape of a defect to be detected by bringing a probe with a sharp tip into proximity with the defect to be detected and scanning as shown in FIG.

Atomic force microscope (AFM: Atomic)
The Force Microscope is an apparatus capable of observing a sample surface at a high magnification based on a principle completely different from that of an optical microscope or an electron microscope which is generally widely used. When a needle with a very sharp tip is brought close to the sample, attractive and repulsive forces act between the two due to various factors. A is to observe the surface shape of the sample using this force.
It is FM, and as the name implies, it is possible to obtain an atomic image utilizing interatomic force depending on the measurement conditions. The probe used for the measurement is made of Si ₃ N ₄ or Si, and has a very fine structure with a length of about 3 μm and a tip radius of 10 to 15 nm.

Next, an AFM measurement system will be described. As shown in FIG. 2 (a), when a sample is slowly brought close to this probe, an attractive force or a repulsive force acts between them at a certain distance, and a cantilever (not shown) with the probe is attached.
Distortion occurs. This distortion is detected by the optical sensor due to the change in the reflection angle of the laser beam applied to the back surface of the lever, and when the probe is scanned on the sample surface, the amount of distortion of the lever becomes constant and the probe and sample The distance between is controlled. Scanning of the sample surface (X, Y directions) and control of the probe-sample distance (Z direction) are performed by the piezo scanner, and an image of the sample surface is obtained by analyzing the voltage applied to each scanner. . One of the features of the atomic force microscope is that information in the height direction of the sample surface has high resolution (0.01 n
m) can be obtained. Also, an image of physical properties such as frictional force and magnetic force can be obtained. Further, it is possible to obtain an image of several thousand times to several million times (atomic level depending on the sample). Also, insulators can be measured without special pretreatment.

When a defect is detected, it is possible to obtain the three-dimensional shape of the defect by confirming the position of the defect, deciding an area where the three-dimensional shape is to be observed, and scanning the probe in the area. First, the probe 31 is scanned in the X direction shown in FIG. 2 while keeping the probe 31 at a constant distance from the defect 32. Once the defect 32 has been scanned in the X direction, the probe 31 is shifted in the Y direction, and the X direction is scanned in the direction opposite to the direction in which the X direction was previously scanned. By repeating this scanning, as shown in FIG. 2B, it is possible to detect the unevenness in the three-dimensional shape scanning region 34 including the entire defect 32. Further, the position information of the defect is stored in advance in the storage device by the defect inspection device, and the position of the defect can be confirmed by reading this information by the defect information reading means 13, and only the defect 32 is scanned. Will be possible. The defect shape detecting means 14 is arranged in the vacuum chamber 1 and is electrically connected to the FIB ion source 5, the ion deflection system 6, the secondary ion detector 4 and the mask control stage 2 so that the defect can be corrected during the correction. It is also possible to observe the place. Since the repaired portion can be observed during the repair, the defect can be repaired accurately and sufficiently.

In this embodiment, an atomic force microscope using a probe is used to measure the shape of the defect, but the present invention is not limited to this. For example, in particular, to measure a minute surface shape. Is a scanning probe microscope (SPM, ST
M), a laser microscope, a white light microscope, etc. can also be used. Further, it is also possible to combine them for more accurate measurement.

When the defect shape detection means 14 detects a defect, the defect shape data is sent to the control processor 8 through the defect correction amount conversion means 9, and the control processor 8 moves the mask control stage 2 to a position where the defect can be observed. To move. At this time, the position information of the defect sent to the control processor 8 is read by the defect information reading means 13, and the information of the moving direction and the moving distance of the stage is transmitted to the mask control stage 2 which is the transport system via the control processor 8. To be done. The mask control stage 2 that has received the information from the control processor 8 moves the stage based on the information and moves the defect to a range where the focused ion beam can be irradiated.

Further, in the three-dimensional shape data of the defect acquired by the defect shape detecting means 14, the three-dimensional shape of the defect is divided in the height direction, and the defect correction amount converting means 9 creates a contour map of the defect. It The defect correction amount at each height is calculated based on this contour map. Figure 3
The defect correction amount conversion means 9 will be described in detail with reference to. A convex defect 42 is formed on the transparent substrate 41. The defect 42 is a foreign material attached to a region on the transparent substrate 41 where the shift layer is not required to be formed or a part of a material forming the shift layer, and has a low light transmittance of Cr and the shift of the halftone phase shift mask. It is a black defect in which the material forming the layer is attached. The defect is not limited to the convex defect, and may be a white defect in which a part of the normal mask pattern is missing. In the case of repairing a black defect, an extraneous deposit is removed by irradiating a focused ion beam while spraying a corrosive gas as a reactive gas on the defect. Further, in the case of repairing a white defect, the carbon film can be made to volume in the defective portion of the pattern by irradiating a focused ion beam while blowing a gas containing carbon as a reactive gas onto the defect.

The data of the three-dimensional shape of the defect obtained by the defect shape detecting means 14 is divided in the height direction, as shown in FIG.
It is divided into a plurality of divided areas 43 as shown in FIG.
A contour map of the defect 42 is created based on the data regarding the height of the divided areas 43, and the three-dimensional shape of the defect 42 is made into a two-dimensional shape. FIG. 3B is an example of a contour map created based on the data obtained by dividing the shape data of the defect 42 in the height direction in the divided region 43. The contour map is a map in which the same height portion is connected by a line and the three-dimensional shape of the defect is two-dimensionalized. Based on the obtained contour map, the correction amount is calculated according to the height of each area of the defect. When the correction amount is known, the irradiation amount or irradiation time of the focused ion beam irradiated to correct the defect is calculated. As in the present embodiment, by detecting the shape of the defect and determining the irradiation condition of the focused ion beam based on the shape, the defect is corrected with high accuracy as compared with the case where the correction is performed based on the data of the phototransferability. It can be performed.

FIG. 4 is a flow chart showing an outline of a mask repairing method for repairing a mask using the mask repairing apparatus of this embodiment. First, the ion beam generated by the FIB ion source 5 scans and controls the photomask 3 through the ion deflection system 6 to detect the secondary electrons emitted from the pattern formed on the photomask 3 by the secondary ion detector 4. Capture with. By irradiating the photomask 3 with a focused ion beam of low energy in this way, a defect is detected and the position of the defect is specified (S101).

As for the information on the position of the defect, the defect position information recorded in advance is read by the defect information reading means 13, and the mask control stage 2 is moved so that the defect can be irradiated with the focused ion beam via the control processor 8. It Since the mask control stage 2 can be moved in the X-Y directions on the plane, the mask control stage 2 is moved so that the defect to be observed falls within the irradiation range of the ion beam. Next, secondary ions emitted from the surface of the photomask by ion beam irradiation are detected by the secondary ion detector 4, and the detected signal is captured as an image by the image observation means 7,
The mask pattern image can be observed. By suppressing the energy of the focused ion beam irradiated when observing the defect to be lower than the energy of the focused ion beam irradiated when correcting the defect, the defect can be observed while suppressing damage to the substrate (S102).

Next, the three-dimensional shape of the defect is measured. Since the position of the defect has been specified in the previous step, the defect shape detecting means 14 measures the three-dimensional shape of the defect.
At this time, since the position of the defect is specified in advance, only the defect can be scanned, and the data of the defect shape can be acquired promptly without scanning an extra area. You can In this embodiment, an atomic force microscope using a probe is used to measure the shape of the defect, but the present invention is not limited to this. For example, in order to measure a minute surface shape, a scanning probe is used. Microscope (SP
M, STM), a laser microscope, a white light microscope, etc. can also be used. Further, it is also possible to combine them to perform more accurate measurement (S103).

Next, among the defect shape data acquired by the defect shape detecting means 14, the data in the height direction of the defect is divided by the defect correction amount converting means 9 (S104). A defect contour map is created by connecting points of the same height in the divided data in the height direction (S10).
5). The defect correction amount conversion means 9 determines irradiation conditions such as the irradiation amount and irradiation time of the focused ion beam based on the contour map (S106). Therefore, the position of the defect in the plane is positioned by the mask control stage 2 on which the photomask is mounted, and the defect is corrected in the height direction (or the depth direction) under the irradiation condition of the focused ion beam. The defect is corrected by adjusting the amount (S107).

After the defect is corrected, the defect shape detecting means 14 measures the defect shape again, and if the correction is surely made, the defect correction is finished (S108).
Here, if it is found that the correction has not been sufficiently performed, a contour map is created again based on the data of the three-dimensional shape, the defect correction amount is recalculated, and the focused ion beam irradiation conditions are optimized. Make corrections. By repeating this process, it is possible to surely correct the defect. Further, even during the irradiation of the focused ion beam, the defects may be corrected by successively irradiating them while measuring the three-dimensional shape of the defects.

[0040]

According to the present invention, the defect can be corrected with high accuracy by observing the defect and correcting the defect. Further, by determining the irradiation condition of the focused ion beam based on the data of the three-dimensional shape of the defect, it becomes possible to correct the defect without causing the defect correction residue or the irradiation damage to the transparent substrate. In particular, even when repairing a transparent protrusion defect that occurs in a Levenson-type phase shift mask that was difficult to repair, by detecting the defect shape without detecting the component elements, the irradiation amount or irradiation of the focused ion beam It is possible to correct with high accuracy by calculating the time and correcting it. Further, by combining the defect shape detection means and the defect correction amount conversion means, the correction amount in the height direction can be set with high accuracy, and the information can be reflected in the irradiation condition of the focused ion beam so that the correction remaining or Irradiation damage to the transparent substrate can be suppressed.

[Brief description of drawings]

FIG. 1 is a structural block diagram showing an outline of a configuration of a photomask correction apparatus according to an embodiment of the present invention.

FIG. 2 is a probe operation diagram showing an operation of the probe when detecting a defect shape of the photomask repairing apparatus according to the embodiment of the present invention.

FIG. 3 is a schematic data processing diagram showing a procedure for dividing defect shape data according to the embodiment of the present invention.

FIG. 4 is a flowchart showing a procedure of a defect repairing method in the embodiment of the present invention.

FIG. 5 is a schematic diagram showing an outline of defects generated on a photomask.

FIG. 6 is a schematic view showing an example of a defect occurring in a halftone type phase shift mask.

FIG. 7 is a schematic diagram showing an example of a defect occurring in a Levenson-type phase shift mask.

[Explanation of symbols]

1 vacuum chamber 2 Mask control stage 3 photo mask 4 Secondary ion detector 5 Ion source 6 Ion deflection system 7 Image observation means 8 control processor 9 Defect correction amount conversion means 10 monitors 11 Input means 12 Output means 13 Defect information reading means 14 Defect shape detection means 31 probe 32 defects 34 Three-dimensional scanning area 41 transparent substrate 42 defects 43 divided areas 111 transparent substrate 112 Halftone shifter layer 113 defects 121 transparent substrate 122 Light-shielding film 123 protrusion defect 124 groove

Claims (10)

[Claims] 1. A mask repairing device for repairing a defect by irradiating a mask with a focused ion beam, comprising defect shape detecting means for detecting a three-dimensional shape of the defect, and data of the three-dimensional shape of the defect. A mask repairing device comprising: a defect repairing amount converting means for converting into a defect repairing amount, and irradiating a focused ion beam based on the repairing amount. 2. The mask repair apparatus according to claim 1, wherein the defect is a black defect or a white defect. 3. The mask correction according to claim 1, wherein the irradiation amount and irradiation time of the focused ion beam are determined based on the correction amount of the defect generated by the defect correction amount conversion means. apparatus. 4. The mask repairing apparatus according to claim 1, wherein the defect is repaired while observing the three-dimensional shape of the defect. 5. The mask repairing apparatus according to claim 1, wherein the mask is a halftone type phase shift mask or a Levenson type phase shift mask. 6. The mask repairing apparatus according to claim 1, wherein the defect shape detecting means is an atomic force microscope. 7. The mask repairing apparatus according to claim 1, wherein the defect repairing amount converting means creates a contour mapping of the defect. 8. The mask repairing apparatus according to claim 1, wherein the focused ion beam is irradiated while a reactive gas is allowed to flow through the defects. 9. A mask repairing method for repairing a defect by irradiating a mask with a focused ion beam, detecting a three-dimensional shape of the defect, and converting data of the three-dimensional shape of the defect into a correction amount of the defect, A mask repairing method comprising irradiating a focused ion beam based on the modification amount. 10. The mask repairing method according to claim 9, wherein the focused ion beam is irradiated while observing the three-dimensional shape of the defect.